using AibisDream.Framework;
using AibisDream.Utility;
using DG.Tweening;
using UnityEngine;
using UnityEngine.EventSystems;

namespace AibisDream
{
    public class CordPull : MonoBehaviour, IInteraction
    {
        private static readonly int ShineFade = Shader.PropertyToID("_ShineFade");
        
        private EventTriggerEx _trigger;
        private SpriteRenderer _sprite;
        private EngineSystem _engineSystem;
        private Vector3 _initPos;
        public float maxDistance;

        private Vector3 _dragPoint;
        private bool _isDragging;

        private void Awake()
        {
            // 记录当前位置
            InitRefs();
        }

        private void InitRefs()
        {
            _initPos = transform.position;

            _trigger = GetComponent<EventTriggerEx>();
            _engineSystem = transform.parent.GetComponent<EngineSystem>();
            _sprite = GetComponent<SpriteRenderer>();
            
            _trigger.Register(EventTriggerType.BeginDrag, OnBeginDrag);
            _trigger.Register(EventTriggerType.EndDrag, OnEndDrag);
            _trigger.Register(EventTriggerType.Drag, OnDrag);
        }

        private void Update()
        {
            if (_isDragging)
            {
                MoveToDragPos();
            }
        }

        private void MoveToDragPos()
        {
            float curY;
            // 如果拖拽点在上方，直接移动
            if (_dragPoint.y > transform.position.y)
            {
                curY = _dragPoint.y;
            }
            // 如果拖拽点在下方，限速移动
            else
            {
                curY = _dragPoint.y;
                var pullDelta = Mathf.Abs(curY - transform.position.y) / maxDistance;
                // 将增量同步给Engine
                _engineSystem.AddAirPress(pullDelta);
            }

            transform.position = new Vector3(transform.position.x, curY, transform.position.z);
        }

        private void OnDrag(BaseEventData data)
        {
            // 这里是一些阻碍拖动的情况
            if (!IsActive) return;
            
            // 正常情况下不会出错
            if (data is not PointerEventData pointerData) return;

            // 设置拖拽目标点
            SetDragTarget(pointerData.position);
        }

        private void OnBeginDrag(BaseEventData data)
        {
            // 这里是一些阻碍拖动的情况
            if (!IsActive) return;
            
            // 首次拖拽后关闭高亮
            if (GlobalVariableKit.IsCordHighLight)
            {
                GlobalVariableKit.IsCordHighLight = false;
                _sprite.material.SetFloat(ShineFade, 0);
            }
            
            // 正常情况下不会出错
            if (data is not PointerEventData pointerData) return;
            // 设置拖拽目标点
            SetDragTarget(pointerData.position);

            // 开始拖动的时候把原有的动画删掉
            transform.DOKill();
            _isDragging = true;
        }

        private void OnEndDrag(BaseEventData data)
        {
            _isDragging = false;
            // 松手后抽回去
            var retractTime = (_initPos.y - transform.localPosition.y) / _engineSystem.engineConfig.returnSpeed;
            transform.DOMove(_initPos, retractTime);
        }

        private void SetDragTarget(Vector3 mousePos)
        {
            var worldPos = CameraKit.GetMouseWorldPos(mousePos);

            var dragY = CommonUtil.Limit(worldPos.y, _initPos.y, _initPos.y - maxDistance);

            _dragPoint = new Vector3(transform.position.x, dragY, transform.position.z);
        }

        public void ActiveShine()
        {
            _sprite.material.SetFloat(ShineFade, 1);
        }

        #region 交互限制相关

        public bool IsActive => _engineSystem.isPullActive;

        public bool IsAvailable => _engineSystem.isAvailable;

        public GameObject GetGameObject()
        {
            return gameObject;
        }

        #endregion
    }
}